Resveratrol inhibits IL-1β-induced stimulation of caspase-3 and cleavage of PARP in human articular chondrocytes in vitro

Resveratrol is a polyphenolic phytoalexin that is present in various fruits, in the skin of red grapes and peanuts. Recent studies have shown that resveratrol exhibits potent antioxidant properties and is able to exert anti-inflammatory and anti-catabolic properties in several cell types. The pro-inflammatory cytokine interleukin-1 beta (IL-1 beta) plays a pivotal role in the pathogenesis of osteoarthritis (OA) in humans and animals. In this article we investigated whether resveratrol is able to block the effects of IL-1 beta, specifically the activation of caspase-3 and subsequent cleavage of poly (ADP-ribose) polymerase (PARP) in human articular chondrocytes. Cultures of human chondrocytes were prestimulated with 10 ng/mL IL-1 beta for 1, 12, and 24 h before being co-treated with IL-1 beta and 100 mu M resveratrol or 50 mu M of the caspase inhibitor Z-DEVD-FMK for 1, 12, and 24 h, respectively in vitro. Resveratrol significantly reduced the IL-1 beta-induced inhibition of expression of cartilage-specific collagen type II and signal transduction receptor beta 1-integrin in a time-dependent manner. Incubation of chondrocytes with IL-1 beta resulted in the activation of caspase-3 and PARP cleavage. These effects were abolished through co-treatment with resveratrol. Furthermore, co-treatment of IL-1 beta-stimulated cells with the caspase inhibitor Z-DEVD-FMK blocked activation of caspase-3 and PARP cleavage, suggesting that this process is a caspase-dependent pathway. In summary, our results confirm that resveratrol is an effective inhibitor of chondrocyte apoptosis in vitro. These findings suggest that this dietary polyphenolic compound may have future applications in the nutraceutical-based therapy of human and animal OA.